
Trouble is you will never really know if her skeletal issues were exacerbated by youthful spaying. Certainly on balance there are definite pro's to having bitches spayed, but the benefits of having it done before puberty in my opinion are not worth the extra risks re growth, increased chance of urinary incontinence, and the mental effects (Peter Pan syndrome).
The increased risks re mammary tumours by having a season or two are more acceptable, especially as if the statistics (which have been challenged, and certainly not in my expereince) are true half of all entire bitches will get them, and of those about half are malignant, but they are very treatable, and with normal care should be spotted when very small.
I have now owned 7 bitches that have had at least one season, and only one ever had a Mamamry tumour, which was removed at pea size when she was five, reapeared at 8 1/2 so that gland was removed. She lived to over 13 1/2 and Cancer did not kill her.
I would print off that article (PDF document) above if you really intend to have words with yoru vet. It may well be news to them.